NGK Iridium IX TR6IX Spark Plugs for C6 Corvette ZR1 LS9
NGK Iridium IX TR6IX spark plugs, stock number 3689, fit the 2009-2013 C6 Corvette ZR1 with the LS9 6.2L supercharged engine. This offer includes eight spark plugs supplied as two packs of four.
Servicing your LS9 starts with a matched set for all eight cylinders. The fine iridium tip supports consistent ignition and resists electrode wear, giving stock ZR1 owners an Iridium IX replacement option with the full V8 quantity in one order. Keep the plug choice tied to the engine configuration you are actually servicing. For a factory-specification ZR1, this is a complete spark-plug order; the condition of the separate wires and coils still needs its own inspection.
Product Details
- NGK stock number: 3689; design code: TR6IX.
- Iridium fine-wire center electrode.
- Eight spark plugs: two packs of four.
- Spark plugs only; plug wires and ignition coils are not included.
- Corrosion-resistant plating: The threaded steel shell uses trivalent metal plating to help resist corrosion and aid removal at a later plug service.
Benefits
- Complete V8 quantity: One order supplies all eight replacement plugs.
- Stable spark: The fine iridium tip supports consistent ignition and resists electrode wear.
- Easier later servicing: Protective shell plating resists corrosion and acts as a release layer when the LS9 plugs are removed again.
Important Notes
- For the factory-supercharged 6.2L LS9 in the 2009–2013 C6 ZR1.
- Verify before fitting: Check TR6IX and stock number 3689 on the replacement-plug packaging, then inspect each plug’s ceramic insulator and electrodes before installation.
- For a modified LS9: Have your engine builder or tuner confirm the plug requirements for the actual pulley, boost and calibration setup before ordering.
- Confirm the installation gap and tightening specification for your exact vehicle. Do not assume the plug's supplied gap is the required setting.
- Check without damaging the tip: Use a round-wire or pin gauge. If adjustment is needed, bend only the ground electrode with the proper tool, keeping pressure off the fine center tip.
- Keep the threads dry: Install these plated plugs without anti-seize or thread lubricant; lubrication alters the effect of the specified tightening torque.
- Follow the tightening procedure: Incorrect torque can damage a plug or interfere with heat transfer. If you are unfamiliar with the work, have a qualified installer perform it.
- Work on a cool engine: Keep the plug holes clean before installation. Dirt at the seating area can interfere with tightening and leave a plug improperly seated.
CORVETTE COMPATIBILITY
- 2009-2013 C6 Corvette ZR1
- LS9 6.2L supercharged engine, stock configuration
- Coupe
Why Buy from Custom Corvette Accessories?
At Custom Corvette Accessories, we’re Corvette owners ourselves, and we offer one-on-one customer service to help you choose parts for your car. Have a question about NGK 3689 TR6IX Iridium IX spark plugs for your C6 Corvette ZR1 LS9? Contact us for personal help before you order.
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